This invention relates to motion detection and more particularly to the detection of movement, such as a contrasting body or interface, in the presence of a noisy background.
The detection of a moving interface is central to a number of problems in the physical and biological sciences. For an example, the growth of a new structure at a first order phase transition and the evolution of a pattern within a turbulent fluid pose serious challenges for their automatic detection. In vision, motion detection is the necessary first step for its interpretation. See, for example, D. Marr, Vision (Freeman, San Francisco, 1982); D. H. Ballard et al., Computer Vision (Prentice Hall, Englewood Cliffs, NJ, 1982) and T. Poggio et al., Nature 317, p. 314 et seq. (1985). The presence of noisy background leads to highly complex algorithms which are not always entirely successful or sufficiently robust. See G. Adiv, IEEE Computer Society Conference on Computer Vision and Pattern Recognition, p. 70 et seq. (IEEE Computer Society Press, Silver Springs, MD, 1985), and T. J. Broida and R. Chellappa, IEEE Computer Society Conference on Computer Vision and Pattern Recognition, p. 82 et seq. (IEEE Computer Society Press, Silver Springs, MD, 1985).
By exploiting the properties of computing arrays made up of locally connected simple cellular processors, one dimensional motion in noisy backgrounds can be accurately detected. It is more relevant, however, to detect two dimensional motion in a fluctuating environment vis a vis one dimensional motion. The extra dimension bring forth the important issue of accurately detecting motion at arbitrary angles in the plane of motion in the presence of noise while utilizing algorithms and architecture to perform the detection function which are basically complicated or complex. An example of the cellular approach to two dimensional detection is shown in R. F. Lyon, VLSI Systems and Computations, edited by H. T. Kung et al., pp. 1-19 (Computer Science Press, Silver Spring, MD, 1985), and U.S. Pat. Nos. 4,521,772 and 4,521,773. However, this scheme requires using uniform regular patterned backgrounds and does not take into consideration a random occurring noise pattern in the presence of the motion being detected. The possibility of noise problems are handled by using an inhibition technique which effectively eliminates any noise interference. The implementation of the technique, however, requires a considerable amount of logic and computation.
A principla object of this invention is to provide a one dimensional or two dimensional motion detection system comprising a plurality of interconnected cellular processing cells of simple architecture and operating under simple algorithm approaches to provide fault tolerant detection of motion in the presence of a random noisy background with reliable output even when some cells may have temporarily failed.